Vitamin C

Definition

Vitamin C is a water-soluble vitamin that is necessary for normal growth and development.

Water-soluble vitamins dissolve in water. Leftover amounts of the vitamin leave the body through the urine. That means you need a continuous supply of such vitamins in your diet.

Alternative Names

Ascorbic acid; Dehydroascorbic acid

Function

Vitamin C is needed for the growth and repair of tissues in all parts of your body. It is used to:

Form an important protein used to make skin, tendons, ligaments, and blood vessels

Heal wounds and form scar tissue

Repair and maintain cartilage, bones, and teeth

Vitamin C is one of many antioxidants. Antioxidants are nutrients that block some of the damage caused by free radicals.

Free radicals are made when your body breaks down food or when you are exposed to tobacco smoke or radiation.

The buildup of free radicals over time is largely responsible for the aging process.

Free radicals may play a role in cancer, heart disease, and conditions like arthritis.

The body is not able to make vitamin C on its own, and it does not store vitamin C. It is therefore important to include plenty of vitamin C-containing foods in your daily diet.

For many years, vitamin C has been a popular remedy for the common cold.

Research shows that for most people, vitamin C supplements or vitamin C-rich foods do not reduce the risk of getting the common cold.

However, people who take vitamin C supplements regularly might have slightly shorter colds or somewhat milder symptoms.

Taking a vitamin C supplement after a cold starts does not appear to be helpful.

Food Sources

All fruits and vegetables contain some amount of vitamin C.

Fruits with the highest sources of vitamin C include:

Cantaloupe

Citrus fruits and juices, such as orange and grapefruit

Kiwi fruit

Mango

Papaya

Pineapple

Strawberries, raspberries, blueberries, cranberries

Watermelon

Vegetables with the highest sources of vitamin C include:

Broccoli, Brussels sprouts, cauliflower

Green and red peppers

Spinach, cabbage, turnip greens, and other leafy greens

Sweet and white potatoes

Tomatoes and tomato juice

Winter squash

Some cereals and other foods and beverages are fortified with vitamin C. Fortified means a vitamin or mineral has been added to the food. Check the product labels to see how much vitamin C is in the product.

Cooking vitamin C-rich foods or storing them for a long period of time can reduce the vitamin C content. Microwaving and steaming vitamin C-rich foods may reduce cooking losses. The best food sources of vitamin C are uncooked or raw fruits and vegetables.

Side Effects

Serious side effects from too much vitamin C are very rare, because the body cannot store the vitamin. However, amounts greater than 2,000 mg/day are not recommended because such high doses can lead to stomach upset and diarrhea.

Too little vitamin C can lead to signs and symptoms of deficiency, including: